Add test_suite_max_parallel option to LLVM

Allow to limit number of parallel test tasks.

Author: Flamefire

easybuild/easyblocks/l/llvm.py

@@ -230,6 +230,8 @@ def extra_options():
             'test_suite_ignore_patterns': [None, "List of test to ignore (if the string matches)", CUSTOM],
             'test_suite_ignore_timeouts': [False, "Do not treat timedoud tests as failures", CUSTOM],
             'test_suite_max_failed': [0, "Maximum number of failing tests (does not count allowed failures)", CUSTOM],
+            'test_suite_max_parallel': [None, "Maximum number LIT tasks to use for tests. "
+                                        "Limitted by the global parallel setting.", CUSTOM],
             'test_suite_timeout_single': [None, "Timeout for each individual test in the test suite", CUSTOM],
             'test_suite_timeout_total': [None, "Timeout for total running time of the testsuite", CUSTOM],
             'use_pic': [True, "Build with Position Independent Code (PIC)", CUSTOM],
@@ -599,9 +601,13 @@ def _configure_final_build(self):
             # OMPT based tools
             self._cmakeopts['OPENMP_ENABLE_OMPT_TOOLS'] = ompt_value
 
-        # Make sure tests are not running with more than 'parallel' tasks
+        # Set parallel LIT tasks. Limit by set max-parallelism and in absence of that
+        # use --mpi-tests to determine if parallelism is desired.
         parallel = self.cfg.parallel
-        if not build_option('mpi_tests'):
+        max_parallel = self.cfg['test_suite_max_parallel']
+        if max_parallel:
+            parallel = min(max_parallel, parallel)
+        elif not build_option('mpi_tests'):
             parallel = 1
         lit_args = [f'-j {parallel}']
         if self.cfg['debug_tests']: